Low-Cost Rotary Blood Pump with ICB Magnetic Support

DESCRIPTION (provided by applicant): An "Inherently Controlled Bearing" (ICB) concept has been demonstrated in a magnetically suspended rotary blood pump intended for use as a permanently implanted ventricular assist device (VAD). The ICB eliminates not only position sensors but also active feedback electronic control of the bearing coil currents, and good efficiency and high stiffness of a prototype ICB has been documented. The specific aim of this Fast-Track proposal is to demonstrate that this innovative technology can be extended to produce a very low cost, yet highly durable, pump for medium-term uses, such as extracorporeal lung support (ECLS), or bridge-to-transplant/recovery use. To accomplish this, several additional innovations will be incorporated in the pump design. Walls between the rotor and stator housings will be introduced to isolate the blood path from the now separable and reusable stators. The motor will be redesigned to provide the speed and power required for the wider range of hydraulic output, and the rotor diameter decreased, reducing viscous drag losses by more than the resulting speed increase and reducing the motor torque output required for a particular hydraulic output. Lower cost materials and manufacturing methods will be incorporated to fabricate this nonpermanent, nonimplanted pump. Success in Phase I will be a prototype with sufficient stiffness in the bearing to resist all imposed shock and vibration loads and a bearing power consumption below 2.5 W, at all operating conditions. The prototype will also demonstrate an ability to pump 5 liter/min at 100 mm-Hg pressure rise with motor power input below 8 W, an ability to pump 4 liter/min at 350 mm-Hg pressure rise with motor power below 25 W, and an ability to pump 9 liter/min at 120 mm-Hg pressure rise, with 40 W maximum power. The advantage of success here is that a common, core technology will become available for blood pump applications. Cost benefits will accrue from this commonality, and in quantities of 1000 or more per year, the simple disposable element can be sold at a price competitive with existing products. Improvements on rates of thrombus formation and bearing durability will also be realized, and the relatively small size would allow use as a wearable bridge-to-transplant/recovery device, it would also offer an alternative for small patients, for transient right ventricle support after LVAD implant, or for marketplaces that cannot afford implantable pump costs.